Detachable spring-anchoring means



March 2l, 1950 F, FENGLER 2,501,384

DETACHABLE SPRING-ANCHORING MEANS Filed Aug. 22, 1946 @all Patented Mar.21, 1950 DETACHABLE SPRING-ANCHORING MEANS Ferdinand Fenglcr, Bristol,Conn., assignor to The E. Ingraham Company, Bristol, Conn., acorporation of Connecticut Application August 22, 1946, Serial No.692,325

1 Claim. 1

The present invention relates in general to timepieces and moreespecially to timepieces having improved spring-anchoring means adaptedto secure the outer free end of the mainspring or alarm-spring of thetimepiece to its frame.

Heretofore the free or outer ends of the mainspring and alarm-spring oftimepieces of the class commonly known as alarm clocks have been madefast by securing the outer ends of the springs to one of the pillars ofthe frame, the securingmeans being quite generally a clamp-member whichis adapted to encircle one of the pillars of the frame and to be securedto the free end of the spring by a rivet. This construction is not onlyrelatively expensive, but necessitates that the entire frame of thetimepiece be disassembled to repair or replace a broken spring.

An object of the present invention is to provide improved means foranchoring the outer free end of a spring to the frame of a timepiece.

A further object is to provide a detachable spring-anchoring means whichwill enable the free end of the spring to be readily secured to anddisengaged from the frame of the timepiece without disassembling theframe.

A still further object of the invention is to provide a detachableelement of the frame which is Aconstructed so as to lockingly engage inan aperture in the outer free end of the mainsprng to anchor the springto the frame of the timepiece.

With the above and other objects in view, as will appear to thoseskilled in the art from the present disclosure, this invention includesall features in the said disclosure which are novel over the prior artand which are not claimed in any separate application.

In the accompanying drawings, in which certain modes of carrying out thepresent invention are shown for illustrative purposes:

Fig. l is a fragmentary plan view of the frame of a timepiece embodyingthe improved springanchoring means of this invention;

Fig. 2 is a. front elevation of the frame showing the spring-anchoringmeans of Fig. 1; and

Fig. 3 is a fragmentary sectional view on the line 3-3 of Fig. 1.

Referring to the drawings which illustrate an exemplary embodiment ofthe invention, the timepiece-frame is indicated generally at I andcomprises front and rear movement-plates I I and I2 held in spacedparallel relationship by pillars I3. Mounted between the front and rearmovement-plates are gear trains comprising a timetrain. indicatedgenerally at I4, and an alarmtrain indicated generally at I5. Thetime-train I4 is one of conventional construction and is driven by theforce of a wound spiral mainspring such as shown at I6, the latter beingsupported on a winding-arbor I'I. Heretofore the mainspring oftimepieces of the class referred to have been supported on thewinding-arbor between the front and rear movement-plates, whichconstruction has required a frame of relatively-large dimension fromfront to back. In the present embodiment, however, as seen in Fig. 2,the mainspring I6 is mounted on the winding-arbor I'I so that its upperface lies in a horizontal plane above the horizontal plane of the rearmovementplate I 2, the edge I 20 of the rear movement-plate I2 adjacentthe mainspring I6 being made arcuate in shape so as to provide clearancefor and to accommodate the inner convolutions of the mainspring I6. Thisconstruction permits the use of a relatively-thin frame-structure.

The lower or forward end of the winding-arbor I1 is rotatably mounted inthe front movementplate II. The upper or rear end of the windingarbor isshown journaled in a bearing-aperture I8 formed in a detachable elementof the frame indicated generally at I9, the rear extremity of thewinding-arbor I'I being provided with the usual Winding-key 20 formanually rotating the arbor I1. The mainspring l B is secured at itsinner end 2I to the winding-arbor II, the connection between the innerend of the spring and the arbor being the usual type of fastening-means22, as shown in Fig. 2.

The opposite or outer free end 23 of the mainspring I6 is adapted to beanchored to the frame I0 in a manner such as to enable the outer end 23of the spring to .be readily attached thereto and removed therefrom withdispatch and Without necessitating the disassembly of the entire frame.To this end, the outer extremity of the mainspring is preferably reducedin width, as shown in Fig. 3, the reduced portion constituting a tongue24 having a radius at its outer end and a longitudinal slot 25. The slot25 is substantially rectangular and closed at both ends, itslongitudinal axis being coincident with the longitudinal axis of thetongue 24.

Referring to the detachable element i9 of the frame, the lattercomprises a substantiallystraight bracket or bridge-member of a lengthto span the clearance space provided by the arcuate edge |20 of the rearmovement-plate and superposed on the top surface thereof, the oppositeends of the bridge-member I9 being secured thereto by suitablefastening-means 3| of the respective posts I3 of the frame. As shown inFig, 1, the bracket or bridge-member i9 is substantiab 1y triangular inshape, its base 26 being substantially parallel with the correspondingopposite edge (not shown) of the frame. The opposite ends of thebridge-member constitute relativelynarroW arm-portions 21 having roundedends, the peripheries of which blend substantially tangentially into thebase 26 of the triangle. The intersection of the periphery of each end27 With its corresponding sloping side 28 of the bridgemernber i9constitutes an abrupt shoulder 29, for the purpose hereinafterdescribed. The portion of the bracket I9 intermediate the 1ins 2'l isstruck up to provide elevated substantiallyplanar bridge 39 which isprovided with the aforesaid bearing-aperture I8 in which the upper endof the winding-arbor l'z' is journaled, the bridge 30 constituting, ineffect, a bearing-plate for the winding-arbor- Referring to 3, the arms2'! of the bridgemember are not quite so Wide as the length of 'therectangular slot 2t in the tongue of the mainspi N, and are slightlyless thick than the Width of the tcngue-aperture 25, as a consequence ofwhich the aperturedetongue 2t of the mainspring is adapted to be slippedover one arm 2l' of the bracket-member and to be lock 'ly engagedtherewith. As will be seen from Fig. l, the normal tendency of the outerend 23 of the mainspring I6 is to unwind in. a counterclockrvisedection, mt any tendency for the outer end oi the spring to unwind isprevented by abutment of the outer end of the spring with the shoulderof the respective arm 21; and engagement or the shoulder 25B at theclosed end of the slot 25 with the adm jacent outer edge of therespective arm 2l.

As pointed out above, the bracket ll is adapted to be detachably securedto the frame by iastening-rneans which, as shown in Fig. comprisesupwardly-projecting threaded-extensions 32 of the posts I3 arranged toextend through suitable apertures 33 in therespective arms 2'1 of thebracket, the apertured arms 2l being secured tothe threaded-extensions3.2 by suitable nuts 3i. in the event the mainspring Iii breaks orshould have to be removed for any other reason. the bracket orbridge-member i5 may he readily unfastened from the iframe IIB of thetimepiece by removing the nuts 3! oi the posts i3, whereupon theapertured end 23 of the spring may be slipped oi of its correspondingarm 2l of the bracket Without disassembling the frame it.

Although the preferred spring-anchoring structure is the bridge-likebracket-member i9 shown in the drawings and which has the additionalfunction of a bearing-plate for the windingarbor II, it is Within thepurview of this invention to anchor the apertured end of the spring I6to a bracket which is detachably secured to one of the posts I3 in themanner described above, or to some other part of the frame I0, but whichis independent of the bridge-like bracket-mem ber I9.

The invention may be carried out in other specic ways than those hereinset forth Without departing from the spirit and essential characteristics of the invention, and the present embodiments are, therefore, tobe considered in all respects as illustrative and not restrictive, andall changes coming Within the meaning and equivalency range of theappended claim are intended to be embraced therein.

I claim:

ln a timepiece having a frame, including a .rear movement-plate having arecessed edge: a geartrain mounted in said frame; a spring for drivinggear-train, springr havin@ a longitudinal aperture at its outer end;sp1in,f-'.vind ing arbor; means to secure the inner end of said springto said winding-arbor to support said spring in said frame in.juxtaposition to the recessed edge of said rear movement-plate with aportion of said spring extending rearwardly oi the plane thereof; andmeans to anchor the outer end of spring comprising a bracket-memberarranged to span the recessed edge oi said rear T'erneutplaire andhaving arm-portions at opposi ends thereof and an intermediatebridgeportion, said .arms being arranged to detaclb ably secure saidbridge-portion to rear moi-.fement-plate and one of said arrn-portionsing in. the longitudinal aperture o spring i a plane substantially atright angles to the plane oi the outer end thereof to anchoithe outerend of the spring, said bridge-portion overlymqthe rearwardly-extendingportion of said spring and constituting a. bearing support lor the outerend of said Winding-arbor.

.FERDINAND FElJGL-ER.

REFERENCES CITE The following references are of record in the le of thispatent:

UNITED STATES PATENTS Number Name Date 1,398,597 Lux Nov. 2Q, 19211,459,343 Porter June 19, 1923

